About two dozen men and women, from college students to retirees, gathered on a recent morning in a darkened room at the Calvert County public schools administration building.

"Treat people as you would want to be treated," the narrator intoned as a video played, instructing the group how to avoid sexual harassment in interactions with students. Two more lessons followed, one on AIDS and another about the realities of child abuse and neglect.

The group, a pool of potential substitute teachers, included Andrea Jones, 20, a Calvert High School graduate. She is taking a semester off from college and wanted the challenge of being back in the classroom -- this time, at the helm.

After the video, Jones said she enjoyed working with children at her church and decided to try substitute teaching. She smiled confidently. "I think I can do it."

According to the Substitute Training Institute at Utah State University, a child spends, on average, a total of one full year of class time with substitute teachers from kindergarten through 12th grade.

Pat Young, the county school system's director of personnel and administrative services, said the district this year began holding training seminars once a month -- compared with three or four times a year in previous years -- and raised the pay to increase the number of candidates. School officials also contacted an organization ofretired teachers as part of the recruiting effort.

In addition to the training seminar, a substitute's introduction to the school system includes fingerprinting and a background check, a substitute teacher's handbook and a host of forms to sign, including a pledge to be drug-free.

At the November seminar, Young stressed to the group the importance of delivering a lesson and keeping students engaged.

"We take this seriously," she said. "I believe you can teach anything as long as you're prepared."

Two previous sessions this fall have attracted a total of about 100 substitutes, Young said. Terry Turner, who calls substitutes each day to match them with a classroom absence at a particular school, said about 206 substitutes are working for the county.

In Southern Maryland, only Calvert County holds monthly training sessions for substitutes. Charles County conducts training twice a year and has a roster of about 475 substitute teachers, said Keith Hettel, the school system's human resources director.

"We never have enough," Hettel said.

St. Mary's County has about 300 substitutes and runs a 30-hour training program twice a year, said human resources assistant Richard A. Smith. It includes two classroom observations and training in how to teach certain academic subjects, depending on a person's area of interest.

"Our idea is to get a sub into a class, to take a lesson plan and make a presentation," Smith said.

Substitute assignments can be short-term -- for a day or two -- or stretch out for a few weeks or more, depending on a school's needs.

Some people remain substitutes for years. Kellie Niemann has filled in as needed daily at Northern High School for almost seven years.

She said she has kept working there for so long because she has enjoyed teaching and getting to know the students.

"To me, it's another adult for them to get to know and trust," Niemann said.

At the Calvert training session, Donnie Alexander, 60, of Solomons, a retiree from United Airlines, said she was a substitute teacher last year in Fairfax County. She is interested in substituting for special education students in Calvert.

"The needs are great, and it's very rewarding," she said.

John Bahr, 53, of Dunkirk, is considering pursuing an education degree and wanted to substitute as a way to test his interests. He said the training that stuck most with him had to do with the importance of being responsible for the students not only in the classroom but in any situation -- including fire drills and other potential emergencies.

"You're in charge," Bahr said.

Pat Young, right, the Calvert County school system's director of personnel, talks with prospective substitutes in training.Elizabeth Dorsey collects forms from Mary Sebian, an applicant to be a substitute teacher in Calvert County, during a training session for potential substitutes in Prince Frederick. The county school system holds the training sessions once a month to encourage applications.Prospective substitute teachers must be fingerprinted, as Elizabeth Dorsey, a personnel secretary for the Calvert County school system, does here for John Tooey.